There is an urgent need for predictive biomarkers in several cancers. In colorectal cancers, KRAS exon 2 mutation analyses were mandatory when considering anti-epidermal growth factor antibody therapy with agents such as cetuximab or panitumumab. However, since the introduction of this testing, a cohort of patients still did not appear to benefit from this therapy. Recently, additional testing for KRAS exon 3 and 4, and NRAS considerably improved the predictive power for therapy success. Therefore, an update of the Belgian guidelines for RAS testing was urgently needed.

(BELG J MED ONCOL 2015;9(5):183–90)